Biomedical subjects

C Yang

Publications and source records attributed to C Yang.

At least 325 records · Page 18Linked to original sources

PubMed1997

Structure/function relationship of the cAMP response element in tyrosine hydroxylase gene transcription.

Expression of tyrosine hydroxylase (TH) is limited to catecholamine-producing neurons and neuroendocrine cells in a cell type-specific manner and is inducible by the cAMP-regulated signaling pathway. Previous results indicated that the cAMP response element (CRE) residing at -45 to -38 base pairs upstream of the transcription initiation site is essential for both basal and cAMP-inducible promoter activity of the 2.4-kilobase or shorter upstream sequence of the TH gene (Kim, K. S., Lee, M. K., Carroll, J. , and Joh, T. H. (1993) J. Biol. Chem. 268, 15689-15695; Lazaroff, M. , Patankar, S., Yoon, S. O., and Chikaraishi, D. M. (1995) J. Biol. Chem. 270, 21579-21589). Here, we further report that the CRE is critical for the promoter activity of the 5.6- or 9.0-kilobase upstream sequences of the rat TH gene, which had been shown to direct the cell-specific TH expression in vivo. To define the structure/function relationship of the CRE in transcriptional activation of the TH gene, we performed saturated mutational analyses of 12 nucleotides encompassing the CRE. Mutation of any nucleotide within the octamer motif results in a significant decrease of both basal and cAMP-inducible transcriptional activity of the TH reporter gene construct. Among the four nucleotides adjacent to the CRE (two 5' and two 3'), only the G residue at the immediate 3' position is important for full transcriptional activity. DNase I footprint analysis indicates a positive correlation between in vivo promoter activity and in vitro interaction between the CRE motif and its cognate protein factor(s). Reconstruction experiments using a TH promoter in which the native CRE was rendered inactive show that the CRE can transactivate transcription in either orientation through a window of approximately 200 base pairs upstream of the transcription initiation site, suggesting that CRE supports transcriptional activation of the TH gene in a distance-dependent manner. Finally, when the distance between the CRE and TATA box was changed by inserting an additional 5 or 10 bases, it was observed that both insertional mutations increased activity by approximately 3-fold. The cAMP inducibility was as intact as the wild type construct. Together, these results are consistent with a model in which transcriptional activation of the TH gene by the CRE requires that it be located within a certain proximity of the CAP site but does not depend on a stringent stereospecific alignment in relationship to the TATA element.

Animals↗

PubMed1997

Glucose-dependency of bradykinin-induced insulin secretion from the perfused rat pancreas.

In order to investigate the glucose dependency of bradykinin (BK)-induced insulin secretion, rat pancreata were perfused in situ with BK (1 microM) for 30 min in the presence of glucose concentrations of 0 - 20 mM. Glucose (6 mM) alone maintained a steady baseline insulin secretion which was 6.7 %/- 0.5 ng/min (n = 4). The rate of insulin secretion in the presence of 0 and 1 mM glucose was approximately 70 - 80% and approximately 60-70% less, respectively, than in the presence of 6 mM glucose. The perfusate glucose concentrations of 10 and 20 mM induced a biphasic and dose-dependent insulin secretion, characterized by a transient increase followed by a sustained phase; the sustained phase was higher than the transient increase. BK failed to change insulin secretion in the absence of extracellular glucose. When BK was administered in 1 mM glucose, it induced a transient insulin release peak which was 2.8-fold of the insulin secretion induced by 6 mM glucose, then the insulin concentrations of the effluents decreased gradually to the levels that were slightly higher than that induced by the 1 mM glucose alone, but lower than that induced by 6 mM glucose. After BK was administered in 6 mM glucose, it induced a transient insulin release peak that was 3.6-fold of the baseline level, and followed by a sustained insulin secretion phase which was approximately 50% higher than that of the 6 mM glucose control group. When BK was perfused with 10 or 20mM glucose, it induced a similar insulin secretion pattern as in the glucose alone groups. However, the combination of glucose (10 or 20 mM) and BK induced a higher transient insulin release peak, which was 7.8- and 12-fold of the baseline level, respectively. Also, the BK-glucose-induced sustained phase was higher than the transient peak. BK caused a greater potentiation of insulin secretion in 20 mM glucose than in 10 mM glucose. Taken together, our findings suggest that 1) BK requires the presence of glucose to stimulate insulin secretion and 2) BK induces insulin secretion in a glucose concentration-dependent manner; the higher the glucose concentration, the greater the potentiation in BK-induced insulin secretion.

Animals↗

PubMed1997

Dose-volume histograms for bladder and rectum.

PURPOSE: A careful examination of the foundation upon which the concept of the Dose-Volume Histogram (DVH) is built, and the implications of this set of parameters on the clinical application and interpretation of the DVH concept has not been conducted since the introduction of DVHs as a tool for the quantitative evaluation of treatment plans. The purpose of the work presented herein is to illustrate problems with current methods of implementing and interpreting DVHs when applied to hollow anatomic structures such as the bladder and rectum. METHODS AND MATERIALS: A typical treatment plan for external beam irradiation of a patient with prostate cancer was chosen to provide a data set from which DVH curves for both the bladder and rectum were calculated. The two organs share the property of being shells with contents that are of no clinical importance. DVHs for both organs were computed using a solid model and using a shell model. Typical treatment plans for prostate cancer were used to generate DVH curves for both models. The Normal Tissue Complication Probability (NTCP) for these organs is discussed in this context. RESULTS: For an eight-field conformal treatment plan of the prostate, a bladder DVH curve generated using the shell model is higher than the corresponding curve generated using the solid model. The shell model also has a higher NTCP. A six-field conformal treatment plan also results in a higher DVH curve for the shell model. A treatment plan consisting of bilateral 120-degree arcs, results in a higher DVH curve for the shell model, as well as a higher NTCP. CONCLUSION: The DVH concept currently used in evaluation of treatment plans is problematic because current practices of defining exactly what constitutes "bladder" and "rectum." Commonly used methods of tracing the bladder and rectum imply use of a solid structure model for DVHs. In reality, these organs are shells and the critical structure associated with NTCP is obviously and indisputably the shell, as opposed to its contents. Treatment planning algorithms for DVH computation should thus be modified to utilize the shell model for these organs.

Humans↗

PubMed1997

Inhibition of transmitter release correlates with the proteolytic activity of tetanus toxin and botulinus toxin A in individual cultured synapses of Hirudo medicinalis.

We have studied the effects of tetanus toxin and botulinus toxin A on neurotransmitter release in the Retzius-->P-cell synapse of the leech and exploited the unique properties of this system, which allow for combined physiological and biochemical analyses in single-cell pairs. The sequences of Hirudo medicinalis synaptobrevin and synaptosomal-associated protein of 25 kDa (SNAP-25), deduced by cDNA cloning, are 61 and 55% identical, respectively, to their corresponding mammalian homologs. Whereas Hirudo synaptobrevin is proteolyzed by tetanus toxin, its SNAP-25 isoform is resistant to botulinus toxin A cleavage because of amino acid substitutions within and around the putative cleavage site. In close correlation, microinjection of tetanus toxin into the presynaptic neuron produced a block of transmitter release, whereas botulinus toxin A had no effect on synaptic transmission. Subsequent immunoblotting of single-cell pairs demonstrated directly that the tetanus toxin-mediated block of exocytosis is accompanied by cleavage of synaptobrevin in the injected neuron, resulting in the generation of a detectable C-terminal cleavage product. Immunoblotting also confirmed the resistance of SNAP-25 to botulinus toxin A cleavage in vivo. Using recombinant proteins, we show that the N-terminal fragment of synaptobrevin released by tetanus toxin, but not its C-terminal membrane-anchored cleavage product, participates with syntaxin and SNAP-25 in synaptic SNAP receptor (SNARE) ternary complex formation in Hirudo. Our data demonstrate a direct correlation between the inhibition of transmitter release and the ability of the neurotoxin to proteolyze its target protein and support the view that SNARE ternary complex formation is an important step leading to synaptic vesicle exocytosis.

Amino Acid Sequence↗

PubMed1997

A post-transcriptional regulatory mechanism restricts expression of the paraneoplastic cerebellar degeneration antigen cdr2 to immune privileged tissues.

Paraneoplastic cerebellar degeneration (PCD) is believed to be an autoimmune disorder initiated by the ectopic expression of a neuron-specific protein in breast and ovarian tumors. PCD antisera was used previously to identify several cerebellar degeneration-related (cdr) genes encoding putative PCD antigens. We have found that the cdr2 gene, which encodes a cytoplasmic leucine zipper protein of unknown function, is expressed in PCD-associated tumors, whereas other cdr genes are not; thus, cdr2 encodes the PCD tumor antigen. To determine whether the expression pattern of cdr2 is consistent with its proposed role in PCD, we have isolated the mouse homolog and examined both the mRNA and protein distribution in adult tissues. We have found that cdr2 mRNA is expressed in almost all tissues, whereas the protein is expressed only in the brain and testis. Within the brain, both the cdr2 mRNA and immunoreactivity are confined primarily to neurons in the cerebellum and brainstem, the regions most affected in PCD. These results suggest first that the tissue-specific expression of cdr2 is regulated at a post-transcriptional level. Moreover, because the brain and testis are considered to be immune-privileged sites, the expression pattern of cdr2 is compatible with the autoimmune model of PCD pathogenesis.

Amino Acid Sequence↗

PubMed1997

The effect of bradykinin on secretion of insulin, glucagon, and somatostatin from the perfused rat pancreas.

To evaluate the effect of bradykinin (BK) on rat islet alpha, beta, and delta cells, the rat pancreas was perfused in situ with BK (1 mumol/L) for 30 minutes via a cannula placed in the celiac artery. Insulin, glucagon, and somatostatin concentrations in the effluent were measured to determine the effect of BK on the secretion of these hormones. The BK concentration of the rat pancreas was also measured. Basal secretion of insulin, glucagon, and somatostatin in medium containing 6 mmol/L glucose was maintained at 6.5 +/- 0.5 ng/mL 124 +/- 8 pg/mL, and 511 +/- 22 pg/mL (n = 12), respectively. BK (1 mumol/L) induced a transient peak that was 3.7-fold of the baseline concentration within 3 minutes, followed by a sustained level that was approximately 50% higher than baseline. BK also transiently increased glucagon secretion with a peak that was 1.7-fold of the baseline concentration within 3 minutes, without a sustained secretion phase. BK caused a reduction in somatostatin secretion within 3 minutes to a level of 60% to 70% of the baseline concentration. The BK concentration of the rat pancreas was 3.42 +/- 1.45 micrograms/g protein (n = 5), which was approximately 3 mumol/L. We concluded that BK stimulated insulin secretion, transiently increased glucagon secretion, and decreased somatostatin secretion during the 30-minute perfusion of the rat pancreas.

Analysis of Variance↗

PubMed1997

Induction of protective antibodies in Saimiri monkeys by immunization with a multiple antigen construct (MAC) containing the Plasmodium vivax circumsporozoite protein repeat region and a universal T helper epitope of tetanus toxin.

Previous attempts in inducing protective immunity against Plasmodium vivax in human volunteers and nonhuman primates with recombinant circumsporozoite (CS) proteins have been unsuccessful, largely due to the failure of generating antibodies against the protective B epitope AGDR in the CS protein repeat region. We report here an immunization study in Saimiri monkeys with a multiple antigen construct (MAC) containing the P. vivax CS protein repeat region and a T helper epitope of tetanus toxin formulated in different adjuvants. Monkeys immunized three times with MAC in copolymer P1005, copolymer P1005 plus RaLPS, or MF-75 had titers of antibodies against CS repeat, sporozoites and the protective B epitope AGDR significantly higher than those immunized with MAC in alum or PBS (P < 0.05). Antibody levels in animals that received P1005 were maintained at high level for 7 months after the last immunization. Upon challenge with 10000 sporozoites 2 weeks after the last immunization, 75% (three of four) of monkeys from the alum group, 50% (three of six) of monkeys from the P1005 plus RaLPS group, 40% (two of five) of monkeys from the P1005 group, 33% (two of six) of monkeys from the MF-75 group, and 17% (one of six) of monkeys from the MAC alone group were fully protected. When immunized animals were challenged again with 30000 sporozoites 22 weeks after the last immunization. 40% (two of five) monkeys from the P1005 group were fully protected. The remaining (three) in this group developed low parasitemia (< 2000 parasites mm-3 of blood) after significantly longer prepatent period (P < 0.05). In addition, 17% (one of six) of monkeys each from the P1005 plus RaLPS and MF-75 groups were also fully protected. Protected animals had higher levels of prechallenge anti-AGDR antibody titers than unprotected (1933 vs 281 for the first challenge, P > 0.05; 21527 vs 196 for the rechallenge, P < 0.05). Anti-AGDR antibody titers were positively correlated with the prepatent period of infected animals (r = 0.42 for the first challenge, P > 0.05; r = 0.60 for the rechallenge, P < 0.05) and negatively correlated with the peak parasitemia (r = -0.39 for the first challenge, P < 0.05; r = 0.50 for the rechallenge, P < 0.05). The results suggested that when combined with the use of potent adjuvants and T helper epitopes, MAC subunit vaccines may potentially offer protection against malaria infection.

Amino Acid Sequence↗

PubMed1997

Evaluation of growth characteristics on blood agar and eosin methylene blue agar for the identification of Candida (Torulopsis) glabrata.

Candida albicans and Candida (Torulopsis) glabrata are the most common species of yeast encountered in the clinical laboratory. In this study, we sought to evaluate simple means of screening cultures for the presence or absence of C. glabrata. Twelve thousand five hundred (12,500) consecutive cultures were evaluated for sufficient yeast growth to warrant identification. When detected (369 isolates), the amount of growth on eosin methylene blue agar (EMB) versus sheep blood agar (BAP) (both incubated in 5% CO2), wet mount morphology, and germ tube production were evaluated. All germ tube-negative yeasts were definitively identified using the Vitek YBC card. Of the 369 yeast isolates included in this study, 225 were C. albicans, 102 C. glabrata, and 42 other Candida species. Growth on EMB was greater than BAP for 92 isolates; all identified as C. glabrata. When EMB growth was equal to or less than BAP, 10 isolates were C. glabrata and 267 were other Candida ssp. An accurate presumptive identification of C. glabrata may be made using the observation of greater growth on EMB versus BAP. When coupled with the germ tube test, the majority of yeast isolates could be identified by these simple methods in our laboratory.

Agar↗

PubMed1997

Crystal structure of human mitochondrial single-stranded DNA binding protein at 2.4 A resolution.

We solved the crystal structure of the homotetrameric single-stranded DNA binding (SSB) protein from human mitochondria at a resolution of 2.4 A. The tetramer is formed by two dimers interacting head-to-head and shows D2 symmetry. Sequence-related tetrameric SSB proteins occur in prokaryotes and eukaryotic mitochondria; this is the first report of an atomic resolution structure of this type of protein. Using biochemical data and analysis of sequence homologies, we were able to correlate the functional properties with structure. We propose that ssDNA wraps around the tetrameric HsmtSSB protein through electropositive channels guided by flexible loops.

Amino Acid Sequence↗

PubMed1997

Synthesis of the Ca(2+)-dependent cell adhesion molecule DdCAD-1 is regulated by multiple factors during Dictyostelium development.

In Dictyostelium discoideum, the cadA gene encodes the cell adhesion molecule DdCAD-1, a protein of M(r) 24,000, which mediates Ca(2+)-dependent cell-cell adhesion during development. We have examined the effects of cAMP, cell-cell contact, and growth conditions on cadA expression. cadA has a unique pattern of expression, which appears to be a combination of the expression patterns of early genes and aggregation-stage genes. Expression of the cadA gene in bacterially grown cells is activated at the beginning of the developmental cycle, followed by a period of rapid DdCAD-1 accumulation. The mRNA level reaches its maximum at 9 h of development and then declines to the basal level at approximately 18 h, while the protein level remains constant after reaching its maximum at 12 h. Pulse-chase experiments have demonstrated that DdCAD-1 has a significantly longer half-life than the average cellular protein. Transcription of the cadA gene is stimulated by exogenous cAMP pulses, leading to a 3- to 5-fold increase in the transcription rate. In the fgdA mutant, which lacks a functional G alpha 2, cAMP fails to enhance cadA expression, suggesting that cAMP stimulates cadA transcription via a G protein-dependent pathway. However, inhibition of cell-cell contact has no effect on the synthesis of DdCAD-1. Growth conditions also have a major influence on cadA expression. Axenically grown cells produce a high level of cadA transcripts during vegetative growth. The mRNA level shows a steady decrease during development and is reduced to the basal level by 12 h. In contrast, the level of DdCAD-1 remains relatively high throughout development, suggesting that axenic growth affects the accumulation of cadA mRNA but not the stability of the protein. These results indicate that multiple mechanisms are involved to maintain a high level of DdCAD-1 during development.

Animals↗

PubMed1997

Tyrosine phosphorylation and Syk activation are involved in thrombin-induced aggregation of epinephrine-potentiated platelets.

Thrombin and epinephrine in combination exert synergistic effects on platelet activation. On the other hand, tyrosine phosphorylation and activation of tyrosine kinases including Syk have been shown to play a critical role in the induction of platelet responses to thrombin stimulation. This study investigated the role of tyrosine phosphorylation and Syk activation in the synergistic mechanisms between thrombin and epinephrine. Although epinephrine alone (4 microM) slightly induced protein-tyrosine phosphorylation and Syk activation, the presence of epinephrine caused a shift to the left in the dose-dependence of thrombin (0.01-0.5 U/ml)-induced tyrosine phosphorylation and Syk activation, as well as platelet aggregation. Phenoxybenzamine, an alpha-adrenoceptor antagonist, canceled this potentiation by epinephrine. Since platelets dominantly express alpha 2-adrenoceptor, this result indicates that epinephrine acts through the occupancy of alpha 2-adrenoceptor. Furthermore, pretreatment with a tyrosine kinase inhibitor, genistein, or a cAMP-elevating agent, prostacyclin (PGI2), significantly reduced these synergistic effects of epinephrine. Taken together, our results suggested that the potentiation by epinephrine may be mediated via enhancement of tyrosine phosphorylation and Syk activation, in part through a decrease of intracellular cAMP levels.

Adrenergic alpha-Agonists↗

PubMed1997

Manipulation of independent synthesis and degradation of polyphosphate in Escherichia coli for investigation of phosphate secretion from the cell.

The genes involved in polyphosphate metabolism in Escherichia coli were cloned behind different inducible promoters on separate plasmids. The gene coding for polyphosphate kinase (PPK), the enzyme responsible for polyphosphate synthesis, was placed behind the Ptac promoter. Polyphosphatase, a polyphosphate depolymerase, was similarly expressed by using the arabinose-inducible PBAD promoter. The ability of cells containing these constructs to produce active enzymes only when induced was confirmed by polyphosphate extraction, enzyme assays, and RNA analysis. The inducer concentrations giving optimal expression of each enzyme were determined. Experiments were performed in which ppk was induced early in growth, overproducing PPK and allowing large amounts of polyphosphate to accumulate (80 mumol in phosphate monomer units per g of dry cell weight). The ppx gene was subsequently induced, and polyphosphate was degraded to inorganic phosphate. Approximately half of this polyphosphate was depleted in 210 min. The phosphate released from polyphosphate allowed the growth of phosphate-starved cells and was secreted into the medium, leading to a down-regulation of the phosphate-starvation response. In addition, the steady-state polyphosphate level was precisely controlled by manipulating the degree of ppx induction. The polyphosphate content varied from 98 to 12 mumol in phosphate monomer units per g of dry cell weight as the arabinose concentration was increased from 0 to 0.02% by weight.

Acid Anhydride Hydrolases↗

PubMed1997

Myxococcus xanthus sasS encodes a sensor histidine kinase required for early developmental gene expression.

Initiation of Myxococcus xanthus multicellular development requires integration of information concerning the cells' nutrient status and density. A gain-of-function mutation, sasB7, that bypasses both the starvation and high cell density requirements for developmental expression of the 4521 reporter gene, maps to the sasS gene. The wild-type sasS gene was cloned and sequenced. This gene is predicted to encode a sensor histidine protein kinase that appears to be a key element in the transduction of starvation and cell density inputs. The sasS null mutants express 4521 at a basal level, form defective fruiting bodies, and exhibit reduced sporulation efficiencies. These data indicate that the wild-type sasS gene product functions as a positive regulator of 4521 expression and participates in M. xanthus development. The N terminus of SasS is predicted to contain two transmembrane domains that would locate the protein to the cytoplasmic membrane. The sasB7 mutation, an E139K missense mutation, maps to the predicted N-terminal periplasmic region. The C terminus of SasS contains all of the conserved residues typical of the sensor histidine protein kinases. SasS is predicted to be the sensor protein in a two-component system that integrates information required for M. xanthus developmental gene expression.

Alleles↗

PubMed1997

The adenovirus E3-10.4K/14.5K complex mediates loss of cell surface Fas (CD95) and resistance to Fas-induced apoptosis.

Cytotoxic T cells use Fas (CD95), a member of the tumor necrosis factor (TNF) receptor superfamily, to eliminate virus-infected cells by activation of the apoptotic pathway for cell death. The adenovirus E3 region encodes several proteins that modify immune defenses, including TNF-dependent cell death, which may allow this virus to establish a persistent infection. Here we show that, as an early event during infection, the adenovirus E3-10.4K/14.5K complex selectively induces loss of Fas surface expression and blocks Fas-induced apoptosis of virus-infected cells. Loss of surface Fas occurs within the first 4 h postinfection and is not due to decreased production of Fas protein. The decrease in surface Fas is distinct from the 10.4K/14.5K-mediated loss of the epidermal growth factor receptor on the same cells, because intracellular stores of Fas are not affected. Further, 10.4K/14.5K, which was previously shown to protect against TNF cytolysis, does not induce a loss of TNF receptor, indicating that this complex mediates more than one function to block host defense mechanisms. These results suggest yet another mechanism by which adenovirus modulates host cytotoxic responses that may contribute to persistent infection by human adenoviruses.

Adenovirus E3 Proteins↗

PubMed1997

Analysis of the murine leukemia virus R peptide: delineation of the molecular determinants which are important for its fusion inhibition activity.

In previous studies, the C-terminal R peptide of the murine leukemia virus (MuLV) Env protein was shown to be a potent inhibitor of viral fusion activity. In the present study, we investigated the molecular determinants in the MuLV Env protein cytoplasmic tail which are important for the fusion inhibition activity of the R peptide. We constructed a series of mutant MuLV env genes which express Env proteins with serial truncations, internal deletions, or amino acid substitutions in the cytoplasmic tail. To analyze their cell fusion activity, we employed a quantitative fusion assay. We found that truncations of up to 7 amino acids from the C terminus of the cytoplasmic tail had no detectable effect on the lack of fusion activity of the full-length Env protein; however, further truncations resulted in a progressive increase in cell fusion activity. Studies of mutant proteins with amino acid substitutions in the cytoplasmic tail showed that Leu-627 plays an important role in fusion inhibition by the R peptide, while most of the other amino acids in the R peptide were not essential for fusion inhibition. Studies of mutant proteins with internal deletions upstream of the cleavage site in the cytoplasmic tail showed that this region is also involved in fusion inhibition by the R peptide, although only to a limited extent. The results are consistent with a model in which the MuLV R peptide exhibits its fusion inhibition activity through interaction with a cellular factor(s).

Amino Acid Sequence↗

PubMed1997

Family and cultural correlates of depression among Chinese elderly.

This study hypothesized that depressive experiences of the elderly could be aggravated by universal factors such as low social status, poor health, financial strain, and unhealthy lifestyle, as well as by factors specific to an indigenous socio-cultural environment (stressful family dynamics) of a given population. Three hundred and fifty Chinese subjects aged 65 or older were interviewed either at their homes or in the geriatric out-patient clinic of Beijing Hospital. Hierarchical logistic regression was used to examine significant predictors of depression. Results showed that certain social status, poor physical health, financial strain, unhealthy lifestyle, and stressful family situation explained 47 percent of the variance in depression. However, stressful family situation alone explained 13 percent of the variance in depression, indicating that family factors were important predictors of depression for Chinese elderly. Furthermore, this study demonstrated for the first time that verbal abuse within Chinese families is a significant correlate of depression among the elderly. Cultural implications of these findings are discussed.

Aged↗

PubMed1997

Protective immunity induced in squirrel monkeys with a multiple antigen construct against the circumsporozoite protein of Plasmodium vivax.

Saimiri boliviensis monkeys were immunized with a multiple antigen construct [(PvCS)2]2(P2)2 directed against the circumsporozoite protein of Plasmodium vivax or a combination of the multiple antigen construct with nonionic copolymer P1005, with P1005 and lipopolysaccharide, with muramyl tripeptide Mf-75, or with alum. Following intravenous challenge with 10,000 sporozoites of the Salvador I strain of P. vivax, 11 of the 26 monkeys were protected against patent parasitemia. Ten additional animals were partially protected. Following rechallenge of the 26 monkeys with 30,000 sporozoites of the homologous strain of parasite, four monkeys were totally protected and nine animals were partially protected.

Adjuvants, Immunologic↗

PubMed1997

[Ventriculo-peritoneal shunts for thirty-two patients with traumatic hydrocephalus].

Thirty-two patients with traumatic hydrocephalus were treated by ventriculo-peritoneal shunts. Twenty-two patients were improved (70%). Among them, seventeen patients showed satisfactory results (53%): ventriculo-peritoneal shunts have good effects and few complications; this method is easy to manipulate for traumatic hydrocephalus. We discussed the important points in operations.

Adolescent↗